Final answer:
Reciprocal recombination between IS elements in inverted orientation leads to the duplication of the transposon and/or any material between direct repeats.
Step-by-step explanation:
When two IS elements in inverted orientation located nearby recombine, the correct answer is reciprocal recombination leads to the duplication of the transposon and/or any material between direct repeats (option c). Reciprocal recombination between inverted repeats results in the creation of a composite transposon, or Tn element, which carries the DNA between the IS elements as part of the transposition process. This process can lead to the duplication of genetic material and the spread of genes, including antibiotic resistance genes, to other DNA in the cell.